Battery sensor device

ABSTRACT

A battery sensor device has a fastening device that can be directly fastened to the pole of a vehicle battery. The battery sensor and the fastening device are combined to an integrated component. The fastening device is fastened to a single pole only and is provided with a terminal that is conventional in motor vehicles. Alternatively or additionally, the component is adapted to conventional battery pole troughs as regards its shape and size.

[0001] The invention relates to a battery sensor arrangement.

[0002] A battery sensor arrangement is known, for example, from U.S.Pat. No. 5,939,861. In this known arrangement, the battery sensor isarranged in an indentation in the battery lid provided specifically forthis battery sensor and has to be fastened to both poles of the battery.

[0003] Diverse arrangements and methods are known for the monitoring,control and automatic control of a motor vehicle wiring system, such asthe energy distribution, the energy control and particularly the loadbalancing of the batteries. According to the application case, normallyat least the measurable variables: battery current, the battery voltageand the battery temperature are required. For sensing the batterycurrent, sensors are normally used in the connection line to thebattery. The battery voltage and the battery temperature are usuallymeasured by means of separate sensors directly at the battery poles oraway from them. Therefore, according to the prior art, normally threecompletely independent devices are used, for which a separateinstallation space has to be created in each vehicle and whoseinformation has to be transmitted for further processing usually tohigher ranking control units.

[0004] With respect to the broader technical background concerningbattery sensor arrangements, reference is made to German Patent DocumentDE 35 32 044 A1 and to International Patent Document WO 99/54744 A1.

[0005] It is an object of the invention to improve a battery sensor ofthe initially mentioned type such that the installation costs and thelogic-related expenditures are reduced and the measuring precision isincreased.

[0006] This object is achieved by means of the characteristics ofclaim 1. Advantageous further developments of the invention are theobjects of the dependent claims.

[0007] By means of the invention, an integrated battery sensor iscreated which can be installed in any vehicle with only a few additionalexpenditures while the required installation space is small. Inaddition, as a result of the compact structural shape and theintegration of several necessary components, the failure probability isreduced.

[0008] The drawing shows an embodiment of the invention.

[0009]FIG. 1a is a top view of a first possible design of the integratedconstructional unit according to the invention consisting of the batterysensor and the fastening device in a two-dimensional representation;

[0010]FIG. 1b is a sectional view B-B of FIG. 1a;

[0011]FIG. 2 is a three-dimensional representation of the first possibleconstruction of the integrated structural unit according to theinvention consisting of the battery sensor and the fastening device;

[0012]FIG. 3 is a more precise schematic representation of the batterysensor consisting of the measuring shunt and the electronic unit;

[0013]FIG. 4 is a more precise schematic representation of theelectronic unit;

[0014]FIG. 5a is a two-dimensional schematic representation of a secondpossible construction of the integrated structural unit according to theinvention consisting of the battery sensor and the fastening device;

[0015]FIG. 5b is a view of a construction slightly modified from that ofFIG. 5a;

[0016] and FIGS. 6a and 6 b are views of additional possibilities forthe fastening of the electronic unit on the measuring shunt;

[0017]FIG. 7a is a view of a first further development of the measuringshun; and

[0018]FIG. 7b is a view of a second further development of the measuringshunt.

[0019]FIG. 1a shows the fastening device of the battery sensorpreferably as a conventional battery brass clamp consisting of a clampbody 1 and a clamping screw 2. The battery sensor 3, 4 is constructedessentially of a measuring shunt 3 and of an electronic unit 4. FIG. 1ashows only the two resistance connections (10 a, 10 b; compare also FIG.2) of the measuring shunt 3, which are constructed as mechanicalcarriers, and the a sprayed plastic material around the electronic unit4. According to the invention, the battery sensor 3, 4 and the fasteningdevice 1, 2 are combined to an integrated structural unit. The fasteningdevice 1, 2 has to be connected only to a single pole of a battery, forexample, to the minus pole. The structural unit, consisting of thefastening device 1, 2 and the battery sensor 3, 4, is adapted withrespect to its shape and size to the known battery pole trough (notseparately shown here) specified according to the Polish DIN 72311 (Part15).

[0020] The first resistance connection 10 a illustrated in FIG. 1a atthe top is conductive; the second resistance connection 10 b illustratedin FIG. 1a at the bottom is fastened in an insulating manner by way ofan insulation part 6 to the clamp body 1. At the second resistanceconnection 10 b, the cable socket of a conventional connection cable canbe connected, for example, by means of a screw 5 and a screw nut 7(compare FIG. 1b) embedded in the insulation part 6. In the presentembodiment, in which the clamp 1, 2 is to be connected to the minus poleof the battery, the connection cable (not illustrated here) connects theoutput-side resistance connection 10 b of the measuring shunt 3 with thevehicle body mass.

[0021] For explaining the invention, FIG. 2 represents athree-dimensional view of the structural unit illustrated in FIGS. 1aand 1 b. Identical components have the same reference numbers.

[0022]FIG. 3 essentially illustrates the details of the measuring shunt3, possible arrangements of a temperature sensor 13, 13 a or 13 b and apossible connection of these components with the electronic unit 4. Themeasuring shut 3 consists of a resistance element 11 and of two planarresistance connections 10 a and 10 b. The resistance connections 10 aand 10 b preferably are copper surfaces of a stable construction. Thematerial of the resistance element 1 preferably is manganin, zeranin(ceranin? translator) or isaohm. Copper and manganin/zeranin/isaohm haveapproximately the same temperature coefficient of expansion as theconventional board material FR4 (mixed material with epoxy resin as themain constituent). This board material is preferably also used for thecarrier board 12 of the electronic unit 2, which is shown in FIG. 3without the sprayed-around plastic material. The carrier board 12 of theelectronic unit 4 according to FIG. 3 can therefore be fastened, similarto the SMD-technology, by way of mere soldering points 14 to theresistance connections 10 a and 10 b. As an alternative, the carrierboard 12 can also be fastened in a conductive manner by way of shortscythe-type lines bent upward by 90° of the transmission connections 10a and 10 b to the measuring shunt 3. The soldering points 14 or theconnections of the scythe-type lines are arranged as closely as possibleto the resistance element 11. By way of the soldering points 14, theresistance element 11 is integrated with respect to the circuit into theelectronic unit 4.

[0023] The electronic unit 4 or the carrier board 12 is connected inFIG. 3 with a temperature sensor 13 for measuring the batterytemperature. Alternative arrangements of the temperature sensor areshown by broken lines by means of reference numbers 13 a and 13 b. In aheat-conducting manner, the temperature sensor 13 is arranged directlyon the clamp body 1, for example, by means of a heat-conducting bondingagent. This arrangement permits a very precise temperature measurementbut requires slightly higher expenditures than the arrangement of thetemperature sensors 13 a and 13 b which are mounted in a heat-conductingmanner on the resistance connection 10 b. In a simplified fashion, thetemperature sensor 13 a is connected with the carrier board 12 by way ofconnection wires. The temperature sensor 13 b is connected with thecarrier board 12, for example, by way of soldering points in order toprevent the connection wires. However, a recess in the carrier board 12may be required for the temperature sensor 13 b.

[0024] The electronic unit or the carrier board 12 has, for example, atwo-pole connector 16. A supply cable to the other pole of the battery,here the plus pole, can be connected to the pin 18 of the connector 16.For example, a bidirectional communication line to other electronicequipment in the motor vehicle can be connected to the pin 17 of theconnector 16. As an alternative, the communication line may also requiretwo pins (for example, when a CAN-bus is used). In a third alternative,the communication can, however, also take place per radio transmission.For reasons of space, instead of a connection by way of a connector 16,a direction connection of the connection lines with the board may alsobe provided (for example, by soldering, bonding or welding). (Thealternatives are not shown here).

[0025] Finally, FIGS. 3 and 4 show a first voltage tap 15 for measuringthe battery voltage U_(batt) which is connected in a conductive mannerwith the battery-pole-side (for example, to the minus pole) resistanceconnection 10 a. The second voltage tap for measuring the batteryvoltage U_(batt) is formed by the pin 18 (for example, to the plus poleof the battery).

[0026]FIG. 4 shows additional details of the carrier board 12 or of theelectronic unit 4. The carrier board 12 or the electronic unit 4 has ameasuring, analyzing and control unit 20. The unit 20 detects thebattery voltage U_(batt), the voltage U between the two soldering points14 and the battery temperature. The battery current (I) can be computedfrom the voltage U. For this purpose, for example, the resistance value(R) of the resistance element 11 is stored in the unit 20. The unit 20preferably has a microprocessor and a memory. The unit 20 may alsocontain conventional amplifiers and A/D analog-to-digital converters formeasurement processing. The unit 20 may determine arbitrary additionalbattery indicator quantities, such as the charge condition or the aging.Furthermore, by way of the communication line, the unit 20 itself cannot only transmit information but can also receive additionalinformation from other equipment and further process this informationtogether with the battery quantities. The communication line and thesupply line to the connector 16 are illustrated in a combined manner asa cable tree 21.

[0027] As a function of the information available to the unit 20, thisunit can control a power switch 19 which can close or open aninterruption present in the resistance connection 10 b. In this case,the battery supply of the motor vehicle can be switched off, forexample, in the event of emergencies. As an alternative thereto, thepower switch 19 can also be integrated in one of the two connectioncables to the plus pole or to the minus pole of the battery and can becontrolled by the unit 20.

[0028] In a supplementary manner, FIG. 5a shows only schematically asecond possible construction of the integrated unit according to theinvention consisting of the battery sensor and the fastening device. Inthis case, the dash-dotted line indicates the bore for the clampingscrew 2. This construction deviates from the first construction only inthat locally the battery sensor 3, 4 is more set off from the clampingscrew 2 and is thereby uncoupled from possible bracing during afastening of the clamp body 1.

[0029]FIG. 5b illustrates a construction which is very similar to FIG.5a but, in the case of which a tapering is provided between the clampbody 1 and the measuring shunt 3, in order to avoid tensions in theclamp body 1.

[0030]FIGS. 6a to 7 b show further development possibilities of themeasuring shunt 3 consisting of the resistance element 11 and the tworesistance connections 10 a and 10 b as well as the fastening of theelectronic unit 4 or its carrier board 12. The resistance connections 10a and 10 b preferably (as in FIG. 3) are copper surfaces of a planarconstruction. The material of the resistance element 1, preferablymanganin or zeranin, is arranged, as in FIG. 3, between the resistanceelements 10 a and 10 b.

[0031] In FIGS. 6a to 7 b, the carrier board 12 of the electronic unit 4(also similar to the SMD-technology) is fastened by way of solderingpoints 14 to the resistance connections 10 a and 10 b. Here, thesoldering points 14 form a long drawn-out line along the edge of thecarrier board 12 in FIG. 6a (and in FIG. 7a, lateral view of FIG. 6a).For this purpose, at least partially open conducting tracks for thesoldering points are provided preferably at the edges of the carrierboard. The soldering lines 14 may also be interrupted or be composed ofspaced points. The further development according to FIG. 6a (or FIG. 7a)requires that the width of the carrier board 12 is not much larger thanthe width of the resistance element 11. The reason is that the solderinghas to be provided as close as possible to the resistance element 11. Inthis case, the construction of the measuring shunt according to FIG. 7ais preferably such that a hollow space is created between the resistanceelement 11 and the carrier board 12. The thickness of the resistanceelement 11 is therefore smaller than that of the resistance connections10 a and 10 b. As a result of this hollow space, it is possible to equipthis carrier board 12 on both sides, if required.

[0032] As an alternative, according to FIGS. 6b (and FIG. 7b, lateralview of FIG. 6b), the carrier board 12 can also be connected as closelyas possible with the resistance element 11 (similar to FIG. 3) bysoldering points 14 at the bottom side of the board 12. In contrast toFIG. 3, in this case, a solid (FIG. 6b, left) or a broken (FIG. 6,right) soldering line is provided for the mechanical stabilization (asin FIG. 6a). By way of the soldering points 14, the resistance element11 is always also integrated in the electronic unit with respect to thecircuit. The further development according to FIG. 6b may be combinedwith the construction of the measuring shunt according to FIG. 7a or 7b. If an equipping of the underside of the carrier board 12 is notrequired, a construction according to FIG. 7b will be possible in thecase of which no hollow space is provided between the resistance element11 and the carrier board 12. In a further development according to FIG.6b and FIG. 7b, the width of the carrier board 12 may also be largerthan the width of the resistance element 11.

[0033] In each further development, bonding points (14), for example, bymeans of an electrically conducting and heat conducting bonding agent,can be provided instead of soldering points (14).

[0034] Therefore, in principle, according to the invention, theelectronic unit 4 or the carrier board 12 of the electronic unit 4 isfastened to the planar resistance connections 10 a and 10 b by means ofan electrically conducting material 14 (such as a solder or a bondingagent). The soldering points or bonding points 14 are therefore used forthe electric or circuit-related integration of the measuring shunt or ofthe resistance element 11 into the electronic unit 4 as well as for themechanical fastening of the electronic unit 4 or its carrier board 12 tothe measuring shunt or to its resistance connections 10 a and 10 b.

1. Battery sensor arrangement having a fastening device which can beconnected directly to a pole of a motor vehicle battery, wherein thebattery sensor (3, 4) and the fastening device are combined to anintegrated structural unit, the fastening device is connected only to asingle pole, the fastening device has a clamp (1, 2) conventional forbattery connection cables in the motor vehicle, and the structural unitis adapted with respect to its size and shape to conventional batterypole troughs.
 2. Battery sensor arrangement according to claim 1,characterized in that the battery sensor (3, 4) consists of a planarmeasuring shunt (3) and of an electronic unit (4), in that the measuringshunt (3) is further developed as a resistance element (11) with tworesistance connections (10 a, 10 b) constructed as mechanical carriers,in that the electronic unit (4) is fastened to the resistanceconnections (10 a, 10 b), and in that the resistance element (11) isintegrated in the electronic unit (4) in a circuit-related manner. 3.Battery sensor arrangement according to claim 1 or 2, characterized inthat the battery sensor (3, 4) consists of a planar measuring shunt (3)and an electronic unit (4), in that the measuring shunt (3) is furtherdeveloped as a resistance element (11) with two resistance connections(10 a, 10 b) constructed as mechanical carriers, in that the electronicunit (4) or the carrier board (12) of the electronic unit (4) isfastened to the planar resistance connections (10 a, 10 b) by means ofan electrically conducting material (14).
 4. Battery sensor arrangementaccording to one of claims 1 to 3, characterized in that the batterysensor (3, 4) is fastened by way of a first resistance connection (10 a)in a conducting manner and is fastened by way of the second resistanceconnection (10 b) in an insulating manner to the clamp body (1), and inthat the connection cable for the motor vehicle supply assigned to apole of a battery can be connected to the second resistance connection(10 b).
 5. Battery sensor arrangement according to one of claims 1 to 4,characterized in that the electronic unit (4) is connected with atemperature sensor (13; 13 a; 13 b) which is arranged in aheat-conducting manner on a resistance connection (10 a, 10 b) ordirectly on the clamp body (1).
 6. Battery sensor arrangement accordingto one of claims 1 to 5, characterized in that the electronic unit (4)has a connector (16) to which at least one supply cable to the otherpole of the battery can be connected.
 7. Battery sensor arrangementaccording one of claims 1 to 6, characterized in that the electronicunit (4) has a connector (16) to which at least one communication lineto other electronic equipment in the motor vehicle can be connected. 8.Battery sensor arrangement according to one of claims 1 to 7,characterized in that the electronic unit (4) has a measuring, analyzingand/or control unit (20) which determines the battery voltage(U_(batt)), the battery current, the battery temperature and/or otherbattery indicator quantities.
 9. Battery sensor arrangement according toone of claims 1 to 8, characterized in that a resistance connection (10b) has an interruption which can be closed by way of a power switch(19), and in that the power switch (19) can be controlled by themeasuring, analyzing and/or control unit (20).